Due to its benefits and traits, the DC computer fan is a good fit for mechanical and electrical equipment. It is also commonly utilized due to its ease and tiny size. These are the explanations for why computer fans are so well-liked:
1. Cheap and limited capacity inverters
The rated value of the current when the inverter continues to operate refers to the peak value of the rectangular wave. Induction motors require sine wave current, while DC motors require rectangular wave current. The current rating of the inverter when it continues to operate generally refers to the effective value of this sine wave. To maintain the control ability of the inverter over the motor current, there should be sufficient difference between the inverter DC voltage and the motor induced electromotive force. In this case, if the peak current of the DC motor and the induction motor are assumed to be equal, the former's power output will be 33% higher than the latter, which means that the same rectifier/inverter can drive a brushless DC motor with a power output 33% higher than the induction motor.
2. High power factor
Its power factor is much higher than that of induction motors, as the excitation magnetic field of DC motors does not require reactive current from the power grid. DC motors can operate at a power factor of 1, which is extremely advantageous for low-power motors. Compared with induction motors, motors not only have higher efficiency and power factor at rated load, but also have advantages at light loads.
3. Low loss and high efficiency
Eliminated the loss caused by the excitation current of the induction motor, and at the same time, the permanent magnet DC motor operates in synchronous mode because it uses permanent magnet excitation. Eliminated the frequency loss of the rotor core of the induction motor. These two aspects make the operating efficiency of permanent magnet DC motors much higher than that of induction motors, and the efficiency improvement of small capacity motors is more significant.
4. Good speed regulation performance and simple control
The speed control of direct current fans is not only simple, but also has better speed control performance compared to variable frequency speed control of induction motors.
